/*
* Mesa 3-D graphics library
*
* Copyright (C) 1999-2007 Brian Paul All Rights Reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included
* in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
* OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
* ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
* OTHER DEALINGS IN THE SOFTWARE.
*/
/**
* \file clear.c
* glClearColor, glClearIndex, glClear() functions.
*/
#include "glheader.h"
#include "clear.h"
#include "context.h"
#include "enums.h"
#include "fbobject.h"
#include "get.h"
#include "macros.h"
#include "mtypes.h"
#include "state.h"
void GLAPIENTRY
_mesa_ClearIndex( GLfloat c )
{
GET_CURRENT_CONTEXT(ctx);
ctx->Color.ClearIndex = (GLuint) c;
}
/**
* Specify the clear values for the color buffers.
*
* \param red red color component.
* \param green green color component.
* \param blue blue color component.
* \param alpha alpha component.
*
* \sa glClearColor().
*/
void GLAPIENTRY
_mesa_ClearColor( GLclampf red, GLclampf green, GLclampf blue, GLclampf alpha )
{
GET_CURRENT_CONTEXT(ctx);
ctx->Color.ClearColor.f[0] = red;
ctx->Color.ClearColor.f[1] = green;
ctx->Color.ClearColor.f[2] = blue;
ctx->Color.ClearColor.f[3] = alpha;
}
/**
* GL_EXT_texture_integer
*/
void GLAPIENTRY
_mesa_ClearColorIiEXT(GLint r, GLint g, GLint b, GLint a)
{
GET_CURRENT_CONTEXT(ctx);
ctx->Color.ClearColor.i[0] = r;
ctx->Color.ClearColor.i[1] = g;
ctx->Color.ClearColor.i[2] = b;
ctx->Color.ClearColor.i[3] = a;
}
/**
* GL_EXT_texture_integer
*/
void GLAPIENTRY
_mesa_ClearColorIuiEXT(GLuint r, GLuint g, GLuint b, GLuint a)
{
GET_CURRENT_CONTEXT(ctx);
ctx->Color.ClearColor.ui[0] = r;
ctx->Color.ClearColor.ui[1] = g;
ctx->Color.ClearColor.ui[2] = b;
ctx->Color.ClearColor.ui[3] = a;
}
/**
* Returns true if color writes are enabled for the given color attachment.
*
* Beyond checking ColorMask, this uses _mesa_format_has_color_component to
* ignore components that don't actually exist in the format (such as X in
* XRGB).
*/
static bool
color_buffer_writes_enabled(const struct gl_context *ctx, unsigned idx)
{
struct gl_renderbuffer *rb = ctx->DrawBuffer->_ColorDrawBuffers[idx];
GLuint c;
GLubyte colorMask = 0;
if (rb) {
for (c = 0; c < 4; c++) {
if (_mesa_format_has_color_component(rb->Format, c))
colorMask |= ctx->Color.ColorMask[idx][c];
}
}
return colorMask != 0;
}
/**
* Clear buffers.
*
* \param mask bit-mask indicating the buffers to be cleared.
*
* Flushes the vertices and verifies the parameter.
* If __struct gl_contextRec::NewState is set then calls _mesa_update_state()
* to update gl_frame_buffer::_Xmin, etc. If the rasterization mode is set to
* GL_RENDER then requests the driver to clear the buffers, via the
* dd_function_table::Clear callback.
*/
void GLAPIENTRY
_mesa_Clear( GLbitfield mask )
{
GET_CURRENT_CONTEXT(ctx);
FLUSH_VERTICES(ctx, 0);
FLUSH_CURRENT(ctx, 0);
if (MESA_VERBOSE & VERBOSE_API)
_mesa_debug(ctx, "glClear 0x%x\n", mask);
if (mask & ~(GL_COLOR_BUFFER_BIT |
GL_DEPTH_BUFFER_BIT |
GL_STENCIL_BUFFER_BIT |
GL_ACCUM_BUFFER_BIT)) {
/* invalid bit set */
_mesa_error( ctx, GL_INVALID_VALUE, "glClear(0x%x)", mask);
return;
}
/* Accumulation buffers were removed in core contexts, and they never
* existed in OpenGL ES.
*/
if ((mask & GL_ACCUM_BUFFER_BIT) != 0
&& (ctx->API == API_OPENGL_CORE || _mesa_is_gles(ctx))) {
_mesa_error( ctx, GL_INVALID_VALUE, "glClear(GL_ACCUM_BUFFER_BIT)");
return;
}
if (ctx->NewState) {
_mesa_update_state( ctx ); /* update _Xmin, etc */
}
if (ctx->DrawBuffer->_Status != GL_FRAMEBUFFER_COMPLETE_EXT) {
_mesa_error(ctx, GL_INVALID_FRAMEBUFFER_OPERATION_EXT,
"glClear(incomplete framebuffer)");
return;
}
if (ctx->RasterDiscard)
return;
if (ctx->RenderMode == GL_RENDER) {
GLbitfield bufferMask;
/* don't clear depth buffer if depth writing disabled */
if (!ctx->Depth.Mask)
mask &= ~GL_DEPTH_BUFFER_BIT;
/* Build the bitmask to send to device driver's Clear function.
* Note that the GL_COLOR_BUFFER_BIT flag will expand to 0, 1, 2 or 4
* of the BUFFER_BIT_FRONT/BACK_LEFT/RIGHT flags, or one of the
* BUFFER_BIT_COLORn flags.
*/
bufferMask = 0;
if (mask & GL_COLOR_BUFFER_BIT) {
GLuint i;
for (i = 0; i < ctx->DrawBuffer->_NumColorDrawBuffers; i++) {
GLint buf = ctx->DrawBuffer->_ColorDrawBufferIndexes[i];
if (buf >= 0 && color_buffer_writes_enabled(ctx, i)) {
bufferMask |= 1 << buf;
}
}
}
if ((mask & GL_DEPTH_BUFFER_BIT)
&& ctx->DrawBuffer->Visual.haveDepthBuffer) {
bufferMask |= BUFFER_BIT_DEPTH;
}
if ((mask & GL_STENCIL_BUFFER_BIT)
&& ctx->DrawBuffer->Visual.haveStencilBuffer) {
bufferMask |= BUFFER_BIT_STENCIL;
}
if ((mask & GL_ACCUM_BUFFER_BIT)
&& ctx->DrawBuffer->Visual.haveAccumBuffer) {
bufferMask |= BUFFER_BIT_ACCUM;
}
assert(ctx->Driver.Clear);
ctx->Driver.Clear(ctx, bufferMask);
}
}
/** Returned by make_color_buffer_mask() for errors */
#define INVALID_MASK ~0x0U
/**
* Convert the glClearBuffer 'drawbuffer' parameter into a bitmask of
* BUFFER_BIT_x values.
* Return INVALID_MASK if the drawbuffer value is invalid.
*/
static GLbitfield
make_color_buffer_mask(struct gl_context *ctx, GLint drawbuffer)
{
const struct gl_renderbuffer_attachment *att = ctx->DrawBuffer->Attachment;
GLbitfield mask = 0x0;
/* From the GL 4.0 specification:
* If buffer is COLOR, a particular draw buffer DRAW_BUFFERi is
* specified by passing i as the parameter drawbuffer, and value
* points to a four-element vector specifying the R, G, B, and A
* color to clear that draw buffer to. If the draw buffer is one
* of FRONT, BACK, LEFT, RIGHT, or FRONT_AND_BACK, identifying
* multiple buffers, each selected buffer is cleared to the same
* value.
*
* Note that "drawbuffer" and "draw buffer" have different meaning.
* "drawbuffer" specifies DRAW_BUFFERi, while "draw buffer" is what's
* assigned to DRAW_BUFFERi. It could be COLOR_ATTACHMENT0, FRONT, BACK,
* etc.
*/
if (drawbuffer < 0 || drawbuffer >= (GLint)ctx->Const.MaxDrawBuffers) {
return INVALID_MASK;
}
switch (ctx->DrawBuffer->ColorDrawBuffer[drawbuffer]) {
case GL_FRONT:
if (att[BUFFER_FRONT_LEFT].Renderbuffer)
mask |= BUFFER_BIT_FRONT_LEFT;
if (att[BUFFER_FRONT_RIGHT].Renderbuffer)
mask |= BUFFER_BIT_FRONT_RIGHT;
break;
case GL_BACK:
/* For GLES contexts with a single buffered configuration, we actually
* only have a front renderbuffer, so any clear calls to GL_BACK should
* affect that buffer. See draw_buffer_enum_to_bitmask for details.
*/
if (_mesa_is_gles(ctx))
if (!ctx->DrawBuffer->Visual.doubleBufferMode)
if (att[BUFFER_FRONT_LEFT].Renderbuffer)
mask |= BUFFER_BIT_FRONT_LEFT;
if (att[BUFFER_BACK_LEFT].Renderbuffer)
mask |= BUFFER_BIT_BACK_LEFT;
if (att[BUFFER_BACK_RIGHT].Renderbuffer)
mask |= BUFFER_BIT_BACK_RIGHT;
break;
case GL_LEFT:
if (att[BUFFER_FRONT_LEFT].Renderbuffer)
mask |= BUFFER_BIT_FRONT_LEFT;
if (att[BUFFER_BACK_LEFT].Renderbuffer)
mask |= BUFFER_BIT_BACK_LEFT;
break;
case GL_RIGHT:
if (att[BUFFER_FRONT_RIGHT].Renderbuffer)
mask |= BUFFER_BIT_FRONT_RIGHT;
if (att[BUFFER_BACK_RIGHT].Renderbuffer)
mask |= BUFFER_BIT_BACK_RIGHT;
break;
case GL_FRONT_AND_BACK:
if (att[BUFFER_FRONT_LEFT].Renderbuffer)
mask |= BUFFER_BIT_FRONT_LEFT;
if (att[BUFFER_BACK_LEFT].Renderbuffer)
mask |= BUFFER_BIT_BACK_LEFT;
if (att[BUFFER_FRONT_RIGHT].Renderbuffer)
mask |= BUFFER_BIT_FRONT_RIGHT;
if (att[BUFFER_BACK_RIGHT].Renderbuffer)
mask |= BUFFER_BIT_BACK_RIGHT;
break;
default:
{
GLint buf = ctx->DrawBuffer->_ColorDrawBufferIndexes[drawbuffer];
if (buf >= 0 && att[buf].Renderbuffer) {
mask |= 1 << buf;
}
}
}
return mask;
}
/**
* New in GL 3.0
* Clear signed integer color buffer or stencil buffer (not depth).
*/
void GLAPIENTRY
_mesa_ClearBufferiv(GLenum buffer, GLint drawbuffer, const GLint *value)
{
GET_CURRENT_CONTEXT(ctx);
FLUSH_VERTICES(ctx, 0);
FLUSH_CURRENT(ctx, 0);
if (ctx->NewState) {
_mesa_update_state( ctx );
}
switch (buffer) {
case GL_STENCIL:
/* Page 264 (page 280 of the PDF) of the OpenGL 3.0 spec says:
*
* "ClearBuffer generates an INVALID VALUE error if buffer is
* COLOR and drawbuffer is less than zero, or greater than the
* value of MAX DRAW BUFFERS minus one; or if buffer is DEPTH,
* STENCIL, or DEPTH STENCIL and drawbuffer is not zero."
*/
if (drawbuffer != 0) {
_mesa_error(ctx, GL_INVALID_VALUE, "glClearBufferiv(drawbuffer=%d)",
drawbuffer);
return;
}
else if (ctx->DrawBuffer->Attachment[BUFFER_STENCIL].Renderbuffer
&& !ctx->RasterDiscard) {
/* Save current stencil clear value, set to 'value', do the
* stencil clear and restore the clear value.
* XXX in the future we may have a new ctx->Driver.ClearBuffer()
* hook instead.
*/
const GLuint clearSave = ctx->Stencil.Clear;
ctx->Stencil.Clear = *value;
ctx->Driver.Clear(ctx, BUFFER_BIT_STENCIL);
ctx->Stencil.Clear = clearSave;
}
break;
case GL_COLOR:
{
const GLbitfield mask = make_color_buffer_mask(ctx, drawbuffer);
if (mask == INVALID_MASK) {
_mesa_error(ctx, GL_INVALID_VALUE, "glClearBufferiv(drawbuffer=%d)",
drawbuffer);
return;
}
else if (mask && !ctx->RasterDiscard) {
union gl_color_union clearSave;
/* save color */
clearSave = ctx->Color.ClearColor;
/* set color */
COPY_4V(ctx->Color.ClearColor.i, value);
/* clear buffer(s) */
ctx->Driver.Clear(ctx, mask);
/* restore color */
ctx->Color.ClearColor = clearSave;
}
}
break;
default:
/* Page 498 of the PDF, section '17.4.3.1 Clearing Individual Buffers'
* of the OpenGL 4.5 spec states:
*
* "An INVALID_ENUM error is generated by ClearBufferiv and
* ClearNamedFramebufferiv if buffer is not COLOR or STENCIL."
*/
_mesa_error(ctx, GL_INVALID_ENUM, "glClearBufferiv(buffer=%s)",
_mesa_enum_to_string(buffer));
return;
}
}
/**
* The ClearBuffer framework is so complicated and so riddled with the
* assumption that the framebuffer is bound that, for now, we will just fake
* direct state access clearing for the user.
*/
void GLAPIENTRY
_mesa_ClearNamedFramebufferiv(GLuint framebuffer, GLenum buffer,
GLint drawbuffer, const GLint *value)
{
GLint oldfb;
_mesa_GetIntegerv(GL_DRAW_FRAMEBUFFER_BINDING, &oldfb);
_mesa_BindFramebuffer(GL_DRAW_FRAMEBUFFER, framebuffer);
_mesa_ClearBufferiv(buffer, drawbuffer, value);
_mesa_BindFramebuffer(GL_DRAW_FRAMEBUFFER, (GLuint) oldfb);
}
/**
* New in GL 3.0
* Clear unsigned integer color buffer (not depth, not stencil).
*/
void GLAPIENTRY
_mesa_ClearBufferuiv(GLenum buffer, GLint drawbuffer, const GLuint *value)
{
GET_CURRENT_CONTEXT(ctx);
FLUSH_VERTICES(ctx, 0);
FLUSH_CURRENT(ctx, 0);
if (ctx->NewState) {
_mesa_update_state( ctx );
}
switch (buffer) {
case GL_COLOR:
{
const GLbitfield mask = make_color_buffer_mask(ctx, drawbuffer);
if (mask == INVALID_MASK) {
_mesa_error(ctx, GL_INVALID_VALUE, "glClearBufferuiv(drawbuffer=%d)",
drawbuffer);
return;
}
else if (mask && !ctx->RasterDiscard) {
union gl_color_union clearSave;
/* save color */
clearSave = ctx->Color.ClearColor;
/* set color */
COPY_4V(ctx->Color.ClearColor.ui, value);
/* clear buffer(s) */
ctx->Driver.Clear(ctx, mask);
/* restore color */
ctx->Color.ClearColor = clearSave;
}
}
break;
default:
/* Page 498 of the PDF, section '17.4.3.1 Clearing Individual Buffers'
* of the OpenGL 4.5 spec states:
*
* "An INVALID_ENUM error is generated by ClearBufferuiv and
* ClearNamedFramebufferuiv if buffer is not COLOR."
*/
_mesa_error(ctx, GL_INVALID_ENUM, "glClearBufferuiv(buffer=%s)",
_mesa_enum_to_string(buffer));
return;
}
}
/**
* The ClearBuffer framework is so complicated and so riddled with the
* assumption that the framebuffer is bound that, for now, we will just fake
* direct state access clearing for the user.
*/
void GLAPIENTRY
_mesa_ClearNamedFramebufferuiv(GLuint framebuffer, GLenum buffer,
GLint drawbuffer, const GLuint *value)
{
GLint oldfb;
_mesa_GetIntegerv(GL_DRAW_FRAMEBUFFER_BINDING, &oldfb);
_mesa_BindFramebuffer(GL_DRAW_FRAMEBUFFER, framebuffer);
_mesa_ClearBufferuiv(buffer, drawbuffer, value);
_mesa_BindFramebuffer(GL_DRAW_FRAMEBUFFER, (GLuint) oldfb);
}
/**
* New in GL 3.0
* Clear fixed-pt or float color buffer or depth buffer (not stencil).
*/
void GLAPIENTRY
_mesa_ClearBufferfv(GLenum buffer, GLint drawbuffer, const GLfloat *value)
{
GET_CURRENT_CONTEXT(ctx);
FLUSH_VERTICES(ctx, 0);
FLUSH_CURRENT(ctx, 0);
if (ctx->NewState) {
_mesa_update_state( ctx );
}
switch (buffer) {
case GL_DEPTH:
/* Page 264 (page 280 of the PDF) of the OpenGL 3.0 spec says:
*
* "ClearBuffer generates an INVALID VALUE error if buffer is
* COLOR and drawbuffer is less than zero, or greater than the
* value of MAX DRAW BUFFERS minus one; or if buffer is DEPTH,
* STENCIL, or DEPTH STENCIL and drawbuffer is not zero."
*/
if (drawbuffer != 0) {
_mesa_error(ctx, GL_INVALID_VALUE, "glClearBufferfv(drawbuffer=%d)",
drawbuffer);
return;
}
else if (ctx->DrawBuffer->Attachment[BUFFER_DEPTH].Renderbuffer
&& !ctx->RasterDiscard) {
/* Save current depth clear value, set to 'value', do the
* depth clear and restore the clear value.
* XXX in the future we may have a new ctx->Driver.ClearBuffer()
* hook instead.
*/
const GLclampd clearSave = ctx->Depth.Clear;
ctx->Depth.Clear = *value;
ctx->Driver.Clear(ctx, BUFFER_BIT_DEPTH);
ctx->Depth.Clear = clearSave;
}
/* clear depth buffer to value */
break;
case GL_COLOR:
{
const GLbitfield mask = make_color_buffer_mask(ctx, drawbuffer);
if (mask == INVALID_MASK) {
_mesa_error(ctx, GL_INVALID_VALUE, "glClearBufferfv(drawbuffer=%d)",
drawbuffer);
return;
}
else if (mask && !ctx->RasterDiscard) {
union gl_color_union clearSave;
/* save color */
clearSave = ctx->Color.ClearColor;
/* set color */
COPY_4V(ctx->Color.ClearColor.f, value);
/* clear buffer(s) */
ctx->Driver.Clear(ctx, mask);
/* restore color */
ctx->Color.ClearColor = clearSave;
}
}
break;
default:
/* Page 498 of the PDF, section '17.4.3.1 Clearing Individual Buffers'
* of the OpenGL 4.5 spec states:
*
* "An INVALID_ENUM error is generated by ClearBufferfv and
* ClearNamedFramebufferfv if buffer is not COLOR or DEPTH."
*/
_mesa_error(ctx, GL_INVALID_ENUM, "glClearBufferfv(buffer=%s)",
_mesa_enum_to_string(buffer));
return;
}
}
/**
* The ClearBuffer framework is so complicated and so riddled with the
* assumption that the framebuffer is bound that, for now, we will just fake
* direct state access clearing for the user.
*/
void GLAPIENTRY
_mesa_ClearNamedFramebufferfv(GLuint framebuffer, GLenum buffer,
GLint drawbuffer, const GLfloat *value)
{
GLint oldfb;
_mesa_GetIntegerv(GL_DRAW_FRAMEBUFFER_BINDING, &oldfb);
_mesa_BindFramebuffer(GL_DRAW_FRAMEBUFFER, framebuffer);
_mesa_ClearBufferfv(buffer, drawbuffer, value);
_mesa_BindFramebuffer(GL_DRAW_FRAMEBUFFER, (GLuint) oldfb);
}
/**
* New in GL 3.0
* Clear depth/stencil buffer only.
*/
void GLAPIENTRY
_mesa_ClearBufferfi(GLenum buffer, GLint drawbuffer,
GLfloat depth, GLint stencil)
{
GET_CURRENT_CONTEXT(ctx);
GLbitfield mask = 0;
FLUSH_VERTICES(ctx, 0);
FLUSH_CURRENT(ctx, 0);
if (buffer != GL_DEPTH_STENCIL) {
_mesa_error(ctx, GL_INVALID_ENUM, "glClearBufferfi(buffer=%s)",
_mesa_enum_to_string(buffer));
return;
}
/* Page 264 (page 280 of the PDF) of the OpenGL 3.0 spec says:
*
* "ClearBuffer generates an INVALID VALUE error if buffer is
* COLOR and drawbuffer is less than zero, or greater than the
* value of MAX DRAW BUFFERS minus one; or if buffer is DEPTH,
* STENCIL, or DEPTH STENCIL and drawbuffer is not zero."
*/
if (drawbuffer != 0) {
_mesa_error(ctx, GL_INVALID_VALUE, "glClearBufferfi(drawbuffer=%d)",
drawbuffer);
return;
}
if (ctx->RasterDiscard)
return;
if (ctx->NewState) {
_mesa_update_state( ctx );
}
if (ctx->DrawBuffer->Attachment[BUFFER_DEPTH].Renderbuffer)
mask |= BUFFER_BIT_DEPTH;
if (ctx->DrawBuffer->Attachment[BUFFER_STENCIL].Renderbuffer)
mask |= BUFFER_BIT_STENCIL;
if (mask) {
/* save current clear values */
const GLclampd clearDepthSave = ctx->Depth.Clear;
const GLuint clearStencilSave = ctx->Stencil.Clear;
/* set new clear values */
ctx->Depth.Clear = depth;
ctx->Stencil.Clear = stencil;
/* clear buffers */
ctx->Driver.Clear(ctx, mask);
/* restore */
ctx->Depth.Clear = clearDepthSave;
ctx->Stencil.Clear = clearStencilSave;
}
}
/**
* The ClearBuffer framework is so complicated and so riddled with the
* assumption that the framebuffer is bound that, for now, we will just fake
* direct state access clearing for the user.
*/
void GLAPIENTRY
_mesa_ClearNamedFramebufferfi(GLuint framebuffer, GLenum buffer,
GLint drawbuffer, GLfloat depth, GLint stencil)
{
GLint oldfb;
_mesa_GetIntegerv(GL_DRAW_FRAMEBUFFER_BINDING, &oldfb);
_mesa_BindFramebuffer(GL_DRAW_FRAMEBUFFER, framebuffer);
_mesa_ClearBufferfi(buffer, drawbuffer, depth, stencil);
_mesa_BindFramebuffer(GL_DRAW_FRAMEBUFFER, (GLuint) oldfb);
}